Figure 1.
Model structure in SEM analyses.
Thin lines stand for effects included in all models, thick lines for relationships that varied within model sets, dashed lines for paths contained only in the model set of hatching success, and the dotted line for the effect of brood size in model sets of nestlings’ body mass and tarsus length.
Figure 2.
Relationship of hatching success with the number of hot days during incubation.
Box plots show the median (thick line), interquartile range (box) and the range of data (whiskers); sample sizes are shown below each box.
Figure 3.
Relationship of hatching success with the number of cold days and length of incubation period.
The warped regression plane was fitted from a linear regression to illustrate the interacting effects of the two predictors on hatching success. Open circles are the data points in 3D space defined by the three variables. Grey dots on the bottom grid of the graph show the relationship between the number of cold days and length of incubation period. Arrows highlight the slopes of the relationships between hatching success and number of cold days when incubation is short (white) or long (black), and between hatching success and length of incubation when number of cold days is high (light-grey) or low (dark-grey).
Figure 4.
Relationship of nestlings' body size with average daily mean temperature and number of hot days.
For illustrative purposes, daily mean temperature was categorized according to its 25%, 50% and 75% percentiles. The number of hot days was dichotomized as few (≤2; white boxes) and many (>2; grey boxes) as the median was zero and the 75% percentile was 2 hot days. Body mass (A) was controlled for date and age of nestings, whereas tarsus length (B) was controlled for brood size and age of nestlings by taking their residuals from linear regressions. Box plots show the median (thick line), interquartile range (box) and the range of data (whiskers); sample sizes (i.e. number of broods) are shown below each box.
Figure 5.
Relationship of nestlings' body mass with the number of dry days before fledging.
Box plots show the median (thick line), interquartile range (box) and the range of data (whiskers); sample sizes are shown below each box.